A bearing number is composed of a basic number and a supplementary code, denoting bearing specifications including bearing type, boundary dimensions, running accuracy, and internal clearance.
Bearing series code
| Bearing type | Bearing series code | Type code | Dimension series code | |
|---|---|---|---|---|
| Width series1） | Diameter series | |||
| Single-row deep groove ball bearing | 67 | 6 | （1） | 7 |
| 68 | 6 | （1） | 8 | |
| 69 | 6 | （1） | 9 | |
| 1602） | 6 | （0） | 0 | |
| 60 | 6 | （1） | 0 | |
| 62 | 6 | （0） | 2 | |
| 63 | 6 | （0） | 3 | |
| 64 | 6 | （0） | 4 | |
| Double-row deep groove ball bearing (with filling slot) |
42 | 4 | （2） | 2 |
| 43 | 4 | （2） | 3 | |
| Single-row angular contact ball bearing | 79 | 7 | （1） | 9 |
| 70 | 7 | （1） | 0 | |
| 72 | 7 | （0） | 2 | |
| 73 | 7 | （0） | 3 | |
| 74 | 7 | （0） | 4 | |
| Double-row angular contact ball bearing (with filling slot) |
32 | （0） | 3 | 2 |
| 33 | （0） | 3 | 3 | |
| Double-row angular contact ball bearing | 52 | 5 | （3） | 2 |
| 53 | 5 | （3） | 3 | |
| Self-aligning ball bearing | 12 | 1 | （0） | 2 |
| 22 | 2 | （2） | 2 | |
| 13 | 1 | （0） | 3 | |
| 23 | 2 | （2） | 3 | |
| 112 | 1 | （0） | 2 | |
| 113 | 1 | （0） | 3 | |
| Single-row cylindrical roller bearing | NU 10 | NU | 1 | 0 |
| NU 2 | NU | （0） | 2 | |
| NU 22 | NU | 2 | 2 | |
| NU 32 | NU | 3 | 2 | |
| NU 3 | NU | （0） | 3 | |
| NU 23 | NU | 2 | 3 | |
| NU 4 | NU | （0） | 4 | |
| Double-row cylindrical roller bearing | NNU 49 | NNU | 4 | 9 |
| NN 30 | NN | 3 | 0 | |
| Single-row needle roller bearing | NA 48 | NA | 4 | 8 |
| NA 49 | NA | 4 | 9 | |
| NA 59 | NA | 5 | 9 | |
| Double-row needle roller bearing | NA 69 | NA | 6 | 9 |
| Tapered roller bearing | 329 | 3 | 2 | 9 |
| 320 | 3 | 2 | 0 | |
| 330 | 3 | 3 | 0 | |
| 331 | 3 | 3 | 1 | |
| 302 | 3 | 0 | 2 | |
| 322 | 3 | 2 | 2 | |
| 332 | 3 | 3 | 2 | |
| 303 | 3 | 0 | 3 | |
| 313 | 3 | 1 | 3 | |
| 323 | 3 | 2 | 3 | |
| Spherical roller bearing | 239 | 2 | 3 | 9 |
| 230 | 2 | 3 | 0 | |
| 240 | 2 | 4 | 0 | |
| 231 | 2 | 3 | 1 | |
| 241 | 2 | 4 | 1 | |
| 222 | 2 | 2 | 2 | |
| 232 | 2 | 3 | 2 | |
| 213 | 2 | 0 | 3 | |
| 223 | 2 | 2 | 3 | |
| Single direction thrust ball bearing | 511 | 5 | 1 | 1 |
| 512 | 5 | 1 | 2 | |
| 513 | 5 | 1 | 3 | |
| 514 | 5 | 1 | 4 | |
| Single direction thrust ball bearing with spherical back face | 532 | 5 | 3 | 2 |
| 533 | 5 | 3 | 3 | |
| 534 | 5 | 3 | 4 | |
| Double direction thrust ball bearing | 522 | 5 | 2 | 2 |
| 523 | 5 | 2 | 3 | |
| 524 | 5 | 2 | 4 | |
| Double direction thrust ball bearing with spherical back faces | 542 | 5 | 4 | 2 |
| 543 | 5 | 4 | 3 | |
| 544 | 5 | 4 | 4 | |
| Spherical thrust roller bearing | 292 | 2 | 9 | 2 |
| 293 | 2 | 9 | 3 | |
| 294 | 2 | 9 | 4 | |
[Notes]
1) Width series codes in parentheses are omitted in bearing series codes.
2) These are bearing series codes customarily used.
3) Nominal outer ring width series (inner rings only are wide).
4) Besides NU type, NJ, NUP, N, NF, and NH are provided.
